Search PubMedSearch

Biomedical subjects

C Lassvik

Publications and source records attributed to C Lassvik.

24 records · Page 2Linked to original sources

Adjuvant intravenous sympathetic block with guanethidine in construction of arteriovenous fistulas for blood access.

A prospective randomized investigation of regional intravenous sympathetic block with guanethidine (RGB) was made in patients undergoing surgical construction of arteriovenous fistula (AVF) for vascular access. The blockade was preoperatively performed on chronically uraemic patients without previous vascular access surgery. The studied data were preoperative forearm blood flow, intraoperative fistula blood flow and flow resistance, and patency rates of AVF. Serial occlusion plethysmography showed a 152% increase in mean forearm blood flow in the RGB group, with significant (p less than 0.001) difference from the controls. The fistula blood flow resistance was decreased (p less than 0.05). The early failure rate was 1/17 among the patients treated with RGB and 3/17 in an otherwise comparable control group. RGB may be useful for reducing early failure rates after construction of AVF, by facilitating blood flow through the fistula.

Adolescent

Angina pectoris in the cold. Effects of cold environment and cold air inhalation at exercise test.

Patients with effort angina and a history of cold intolerance performed brief submaximal exercise bicycle test in various temperatures with separation of inspiration and room air. Exposure to a cold room (-10 degrees C) and inhalation of very cold air(- 35 degrees C) in a normal room caused a significant decrease in maximal workload. Heart rate, systolic blood pressure, and rate-pressure product were significantly higher during exercise when compared with findings in the normal room. The decrease in maximal workload correlated significantly to the increase in heart rate and rate pressure product during exercise in both conditions, and to the increase in systolic blood pressure at exposure to a cold room. Exposure to 10 and 0 degree C environmental temperature and inhalation of moderately cold air (- 10 degrees C) did not cause any significant changes in maximal workload, heart rate, blood pressure, or rate pressure product during exercise, compared to the findings in the normal room. In conclusion, skin cooling seems to be far more important in its effect on heart load and the working capacity in patients with effort angina than inhalation of moderately cold air; inhalation of very cold air, however, does cause changes in working capacity similar to those of exposure to a cold environment. Increase in heart work during exercise is likely to cause the decrease in working capacity observed both with skin cooling and cold air inhalation.

Angina Pectoris

Effects of various environmental temperatures on effort angina.

Eleven patients with effort angina and a history of cold intolerance performed short-term bicycle exercise tests at various room temperatures, 20, 10, 0 and -10 degrees C, and a few patients also at -30 degrees C. A significant reduction of maximal working capability (expressed as maximal work load, MWL), limited by moderately severe angina, was found at -10 degrees C (7% +/- 1, SEM, P less than 0.05) compared with normal room temperature. At 0 and 10 degrees C changes of MWL were small and not significant, and at -30 degrees C no further decrease of MWL was seen. About half of the patients, however, showed a tendency toward a decrease in MWL with decreasing environmental temperature, and and the decrease in MWL correlated significantly with an increase in rate pressure product (RPP) during exercise at both 0 and -10 degrees C. Thus, the decrease in working capability on exposure to cold could be explained by an increase in heart work. Warming up effects of exercise, counteracting the cold-induced increase in peripheral vascular resistance, were indicated by a diminishing difference in systolic blood pressure between a cold and normal environment with increasing work time.

Angina Pectoris

Reproducibility of work performance at serial exercises in patients with angina pectoris.

The reproducibility of serial upright exercises in patients with ischaemic heart disease was tested. Five short term exercises (4--8 min) with continuous load increase and with 30 min rest intervals between tests were used. No tendency to change was found concerning work time to appearance of angina (APT), maximal working time (MWT) or time for disappearance of angina after exercise (DPT). The coefficient of variation was low for APT and MWT but considerably higher for DPT, being 9, 5 and 27%, respectively. MWT was considered as the end-point of choice. The ST depression at MWT showed no tendency to change and the variation was moderate (14%), while at APT and DPT the variation was high (52%), but, likewise, with no tendency to change. The maximal heart rate increased slightly and significantly (P less than 0.001), while the maximal blood pressure was constant throughout tests, thus the maximal rate pressure product tended to increase. This indicates a slight improvement of the myocardial performance at serial exercises, which, however, does not affect the reproducibility of the anginal reaction.

Angina Pectoris

Restenosis and occlusion after carotid surgery assessed by duplex scanning and digital subtraction angiography.

In a study of 140 patients operated upon with 143 carotid endarterectomies (mean follow-up time 5.2 +/- 2.3 years, range 1 month - 9.3 years), vessel morphology was examined with duplex scanning in 113 patients and with digital subtraction angiography (DSA) in 82 patients. The operative mortality was 1.4%; persisting stroke morbidity 3.6% and the combined operative mortality/morbidity 5%. During the follow-up time a further 20 patients (14.5%) died, 13 had new strokes and 14 new TIAs. By life table analysis, the annual rate of stroke including the operative period was 2.7% (1.7% on the operated side and 1.0% on the non-operated side). Fourteen new occlusions (12%) of the operated carotid artery was found and restenosis (greater than 50%) in 13 patients (11.2%). Progression of the atherosclerotic disease in the contralateral non-operated carotid artery was found in 41 patients (37%) including 3 new occlusions. Agreement DSA/duplex was 88% on the operated side and 92% on the non-operated side. New strokes or TIAs on the operated side were more common in patients with occlusions or restenosis (p less than 0.05), whereas no symptoms were referable to occlusions on the non-operated side. Risk factor analysis revealed an increased risk of atherosclerotic progression on the non-operated side in smokers and those with two or more risk factors. The risk of restenosis in the operated carotid artery was higher in females (p less than 0.025).

Carotid Arteries